|
|
Creator | Title | Description | Subject | Date |
176 |
|
Chaudhuri, Reaz A. | Three-dimensional singular stress field at the front of a crack and lattice crack deviation (LCD) in a cubic single crystal plate | A novel eigenfunction expansion technique, based in part on separation of the thickness variable, is developed to derive three-dimensional asymptotic stress fields in the vicinity of the front of a semi-infinite through-crack weakening an infinite plate made of a homogeneous cubic single crystal. C... | | 2010-05-12 |
177 |
|
Tiwari, Ashutosh | CuBO2: a p-type transparent oxide | The authors report the synthesis of CuBO2, a p-type transparent oxide belonging to Cu-delafossite family. High quality thin films of CuBO2 were deposited on c-plane sapphire substrates by pulsed laser deposition technique. Detailed structural, optical, and electrical characterizations on these films... | Transparent conducting oxides; Delafossite series; CuBO2 | 2007 |
178 |
|
Liu, Feng | Unique dynamic appearance of a Ge-Si Ad-dimer on Si(001) | We carry out a comparative study of the energetics and dynamics of Si-Si, Ge-Ge, and Ge-Si ad-dimers on top of a dimer row in the Si(001) surface, using first-principles calculations. The dynamic appearance of a Ge-Si dimer is distinctively different from that of a Si-Si or Ge-Ge dimer, providing a ... | Ge-Si Ad-dimer; Si(001); First-principles calculations; Energetics | 2000-12 |
179 |
|
Liu, Feng | Physical origin of hydrogen-adsorption-induced metallization of the SiC surface: n-type doping via formation of hydrogen bridge bond | We perform first-principles calculations to explore the physical origin of hydrogen-induced semiconductor surface metallization observed in β-SiC(001)-3 x 2 surface. We show that the surface metallization arises from a novel mechanism of n-type doping of surface band via formation of hydrogen bri... | Metallization; Hydrogen adsorption; SiC; n-type doping; Hydrogen bridge bond | 2005-10 |
180 |
|
Liu, Feng | Liu et al reply | In our Letter [1], we have demonstrated the plausibility of a structure for ?-cristobalite SiC2 consisting of domains of I Aid symmetry, and provided strong evidence against other proposed models, based on first-principles total energy and lattice dynamics calculations. We are pleased that the Auth... | beta-Cristobalite SiO2; Rigid unit modes; RUM; Transient domain formation | 1993 |
181 |
|
Chaudhuri, Reaz A. | Transverse shear stress distribution through thickness near an internal part-through elliptical hole in a stretched plate | A semi-analytical post-processing method, termed the equilibrium/compatibility method here, is used for computation of hitherto unavailable through-thickness variation of transverse shear stresses in the vicinity of the circumferential re-entrant corner line of an internal part-through elliptical ... | | 2010-03 |
182 |
|
Liu, Feng | Determination of the Ehrlich-Schwoebel barrier in epitaxial growth of thin films | We demonstrate an approach for determining the "effective" Ehrlich-Schwoebel (ES) step-edge barrier, an important kinetic constant to control the interlayer mass transport in epitaxial growth of thin films. The approach exploits the rate difference between the growth and/or decay of an adatom and a... | Ehrlich-Schwoebel barrier; Epitaxial growth; Step-edge barrier; Adatoms | 2006-11 |
183 |
|
Liu, Feng | Magnetism of Al-Mn quasicrystals | The effect of symmetry and concentration of Mn on the magnetism of Al-Mn quasicrystals has been investigated through self-consistent density-functional calculations using molecular clusters and supercell band-structure schemes. A single Mn atom surrounded by 54 Al atoms in an icosahedral or a cuboct... | Al-Mn quasicrystals; Self-consistent; Density-functional calculations | 1993-07 |
184 |
|
Tiwari, Ashutosh | Self-aligned passivated copper interconnects: a novel technique for making interconnections in ultra large scale integration device applications | We have developed a technique to grow self-aligned epitaxial Cu/MgO films on Si (100) using a Pulsed Laser Deposition Method. In this method we deposit a uniform film of Cu/Mg (5-7%) alloy over Si (100) at room temperature using TiN as an intermediate buffer layer. As a result of HRTEM (with spatial... | Passivated copper interconnects; Diffusion barriers; Copper diffusion; Tantalum nitride | 2002 |
185 |
|
Scarpulla, Michael | SnS thin-films by RF sputtering at room temperature | Tin monosulfide (SnS) is of interest as a potential solar cell absorber material. We present a preliminary investigation of the effects of sputtering conditions on SnS thin-film structural, optical, and electronic properties. Films were RF sputtered from an SnS target using an argon plasma. Resi... | | 2011 |
186 |
|
Stringfellow, Gerald B.; Shurtleff, James Kevin | Use of surfactant Sb to induce triple period ordering in GaInP | A surfactant is used to induce an ordered structure in an epitaxial layer. The addition of small amounts of triethylantimony during the organometallic vapor phase epitaxy growth of GaInP on 001 GaAs substrates is shown to remove CuPt ordering with a resultant increase in band gap energy. Increasi... | Organometallic; Thermodynamics; Surfactant | 2000-03-13 |
187 |
|
Liu, Feng | Modified Timoshenko formula for bending of ultrathin strained bilayer films | Mechanical bending of nanoscale thin films can be quite different from that of macroscopic thick films. However, current understanding of mechanical bending of nanoscale thin strained bilayer films is often limited within the Timoshenko model [Timoshenko, J. Opt. Soc. Am. 11, 233 (1925)], which was ... | Timoshenko formula; Bending theory; Ultrathin films; Strained nanoscale thin films; Nanofilms | 2008 |
188 |
|
Stringfellow, Gerald B. | Electron mobility in compensated GaAs and AlGaAs | The dependence of electron mobility on temperature in GaAs and Al Ga As indicates that for cimpensated material a term having causes a significant reduction in the mobility measured at high temperatures. The magnitude of the term in mobility, denoted is found to be linearly proportional to the compe... | Unspecified mobility; Reduced mobility; Space charge regions | 1980 |
189 |
|
Scarpulla, Michael | Ferromagnetic Ga1-xMnxAs produced by ion implantation and pulsed-laser melting | We demonstrate the formation of ferromagnetic Ga1-xMnxAs films by Mn ion implantation into GaAs followed by pulsed-laser melting. Irradiation with a single excimer laser pulse results in the epitaxial regrowth of the implanted layer with Mn substitutional fraction up to 80% and effective Curie tempe... | Gallium arsenide; Ferromagnetic semiconductors; Remanent magnetization | 2003 |
190 |
|
Liu, Feng | Quantum size effect on the magnetism of finite systems | The magnetic moments of the ferromagnetic transition metals Fe, Co, and Ni confined to one-dimensional chains are found to fluctuate with increasing chain length before converging to the infinite limit. This quantum size effect is derived from a simple first-principles theory that we have developed... | Quantum size; Finite systems; Ferromagnetic transition metals; Magnetic moments; Fe; Co; Ni; Molecular-orbital approach | 1990-07 |
191 |
|
Liu, Feng | Stability of doubly charged transition-metal dimers | The spatial dependence of the interaction potentials in doubly charged dimers of transition-metal atoms has been calculated by use of both the tight-binding and the self-consistent-field linear combination of atomic orbitals-molecular orbitals methods. The study reveals an interesting correlation be... | Doubly charged; Transition metal dimers; Spatial dependence; Interaction potentials; Metastability | 1987-11 |
192 |
|
Tiwari, Ashutosh | Electrical properties of transparent and conducting Ga doped ZnO | In this paper, we report on the metal-semiconductor transition behavior observed in transparent and conducting ZnO:Ga films grown by pulsed-laser deposition. The electrical resistivity measurements were carried out on ZnO films with varying Ga concentration in the temperature range of 14 to 300 K. ... | Transparent conducting oxides; ZnO; Gallium; Metallic conductivity | 2006 |
193 |
|
Stringfellow, Gerald B. | Influence of Sb, Bi, Tl, and B on the incorporation of N in GaAs | GaAs:N is an interesting material for many devices due to its unique compositional variation of band gap. Small amounts of N lead to a strong decrease in band gap energy as well as lattice constant. The further addition of In or Sb leads to quaternary alloys with band gap energies below 1.4 eV latti... | Antimony; Gallium Arsenide; Nitrogen | 2002 |
194 |
|
Scarpulla, Michael | Synthesis and optical properties of II-O-VI highly mismatched alloys | We have synthesized ternary and quaternary diluted II-VI oxides using the combination of O ion implantation and pulsed laser melting. CdOxTe12x thin films with x up to 0.015, and the energy gap reduced by 150 meV were formed by O1-implantation in CdTe followed by pulsed laser melting. Quaternary Cd0... | Highly mismatched alloys; Cadmium telluride; Zinc telluride; Thermal annealing; Anticrossing; Photomodulation spectroscopy | 2004 |
195 |
|
Stringfellow, Gerald B. | Surface photoabsorption study of the effect of V/III ratio on ordering in GaInP | Cu-Pt ordering is widely observed in Ga0.5In0.5P layers grown by organometallic vapor phase epitaxy. The degree of order is a strong function of the input partial pressure of the phosphorus precursor, i.e., the V/III ratio, during growth. By observing the surface structure using in situ surface p... | Degree of order; Photoluminescence; Transmission electron microscopy | 1996 |
196 |
|
Scarpulla, Michael | Compensation-dependent in-plane magnetization reversal processes in Ga1-xMnxP1-ySy | We report the effect of dilute alloying of the anion sublattice with S on the in-plane uniaxial magnetic anisotropy and magnetization reversal process in Ga1−xMnxP as measured by both ferromagnetic resonance (FMR) spectroscopy and superconducting quantum interference device (SQUID) magnetometry. ... | Ferromagnetic semiconductors; Nonmagnetic compensation | 2008-12 |
197 |
|
Scarpulla, Michael | Ferromagnetism in Ga1-xMnxP: evidence for inter-Mn exchange mediated by localized holes within a detached impurity band | We report an energy gap for hole photoexcitation in ferromagnetic Ga1-xMnxP that is tunable by Mn concentration (x ≤ 0:06) and by compensation with Te donors. For x ~ 0:06, electrical transport is dominated by excitation across this gap above the Curie temperature (TC) of 60 K and by thermally a... | Gallium Phosphide; Ferromagnetism; Mn impurity band | 2005-11 |
198 |
|
Liu, Feng | Coulomb sink: a novel Coulomb effect on coarsening of metal nanoclusters on semiconductor surfaces | We propose the concept of a ‘‘Coulomb sink'' to elucidate the effect of Coulomb charging on coarsening of metal mesas grown on semiconductor surfaces.We show that a charged mesa, due to its reduced chemical potential, acts as a Coulomb sink and grows at the expense of neighboring neutral mesas. ... | Coulomb sink; Coulomb effect; Metal nanoclusters; Semiconductor surface; Pb mesas | 2004-09 |
199 |
|
Stringfellow, Gerald B.; Williams, Clayton C. | Spatial mapping of ordered and disordered domains of GaInP by near-field scanning optical microscopy and scanning capacitance microscopy | Imaging of topography, locally induced photoluminescence and Fermi-level pinning in adjacent ordered and disordered domains on a cleaved GaInP sample is performed using a near-field scanning optical microscope and scanning capacitance microscope at room temperature in air. Highly localized photolumi... | Gallium Phosphides; Surface Structure; Photoluminescence | 1996-04-13 |
200 |
|
Stringfellow, Gerald B. | Effect of step structure on ordering in GaInP | Examines the effect of step structure on ordering in gallium indium phosphite (GaInP) using atomic force microscopy. Coverage of the surface by islands several monolayers in height with elongated direction; Formation of the edges of the islands; Role of the observations in explaining the nature of t... | Gallium indium phosphite (GaInP); Twin boundaries | 1995-11-12 |